Beam-based pdcch transmission in nr

ABSTRACT

Systems, methods and instrumentalities are disclosed for beam-based PDCCH Transmission in NR. Control resource sets may be assigned for multi-beam control transmission. A PDCCH may be transmitted with multiple beams. CCEs may be mapped for multi-beam transmission. DCI may support multi-dimensional transmission with primary and secondary dimensions. Search space may support multi-beam, multi-TRP transmission.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional Application No.62/500,645, filed May 3, 2017, U.S. Provisional Application No.62/519,555, filed Jun. 14, 2017, U.S. Provisional Application No.62/543,087, filed Aug. 9, 2017, and U.S. Provisional Application No.62/599,124, filed Dec. 15, 2017, the contents of which are incorporatedby reference herein their entireties.

BACKGROUND

Mobile communications continue to evolve. A fifth generation may bereferred to as 5G. A previous (legacy) generation of mobilecommunication may be, for example, fourth generation (4G) long termevolution (LTE). Mobile wireless communications implement a variety ofradio access technologies (RATs), such as New Radio (NR). Use cases forNR may include, for example, extreme Mobile Broadband (eMBB), Ultra HighReliability and Low Latency Communications (URLLC) and massive MachineType Communications (mMTC).

SUMMARY

Systems, methods and instrumentalities are disclosed for beam-basedPDCCH Transmission in NR. A beam-based control resource set (CORESET orcoreset) configuration may be used. Control resource sets may beassigned for multi-beam control transmission. A PDCCH may be transmittedwith multiple beams. CCEs may be mapped for multi-beam transmission.Per-symbol interleaving and across symbol interleaving may be used. Theeffective search space may be reduced for per-symbol interleaving. DCImay support multi-dimensional transmission with primary and secondarydimensions. Search space may support multi-beam, multi-TRP transmission.

A wireless transmit/receive unit (WTRU) may have a computer processorthat is configured to determine a PDCCH. The WTRU processor beconfigured to receive a PDCCH transmission, from a wirelesscommunication system, that includes a control resource set (CORESET)configuration comprising a resource group (REG) bundle; determinewhether the REG bundle is interleaved within symbols or across symbols;detect the REG bundle using a beam corresponding to the REG bundle, ifthe WTRU determined that the REG bundle is interleaved across symbols;and/or determine a multibeam PDCCH using the detected REG bundle andmultiple beams associated with the PDCCH transmission.

The WTRU processor may be configured to determine that a received REGbundle is bundled in frequency, thereby indicating to the WTRU that thePDCCH transmission is a multibeam transmission.

The WTRU processor may be configured to detect the REG bundle using abeam corresponding to the REG bundle and quasi collocated (QCL)information for the REG bundle, if the WTRU determined that the REGbundle is interleaved across symbols.

The WTRU processor may be configured to determine that the receivedPDCCH transmission is a multibeam transmission by determining that theWTRU received a plurality of QCL information corresponding to multipleOFDM symbols in the received PDCCH transmission.

The CORESET configuration may include one or more of a CORESET size, atype of REG bundling, a transmission mode, a set of aggregation levels,a set of DCI information sizes, a number of PDCCH candidates, the QCLinformation, and an indication of whether the CORESET is single-beam ormultibeam. The QCL information may include one or more of average gain,average delay, doppler shift, doppler spread, and spatial receiverparameters. The CORESET configuration may include an indication of amode of interleaving REG bundles.

The WTRU processor may be configured to detect the REG bundle usingPBCH/SYNC beam tracking if the WTRU determined that the REG bundle wasinterleaved within symbols.

The WTRU processor may be configured to determine a single-beam PDCCHusing deinterleaving of the detected REG bundle.

The WTRU processor may be configured to determine, from the CORESETconfiguration whether the mode of interleaving REG bundles is one oftime-first bundling without interleaving, time first bundling withinterleaving, frequency first bundling with per-symbol interleaving, andfrequency first bundling with across symbol interleaving.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a system diagram illustrating an example communicationssystem in which one or more disclosed embodiments may be implemented.

FIG. 1B is a system diagram illustrating an example wirelesstransmit/receive unit (WTRU) that may be used within the communicationssystem illustrated in FIG. 1A according to an embodiment.

FIG. 1C is a system diagram illustrating an example radio access network(RAN) and an example core network (CN) that may be used within thecommunications system illustrated in FIG. 1A according to an embodiment.

FIG. 1D is a system diagram illustrating a further example RAN and afurther example CN that may be used within the communications systemillustrated in FIG. 1A according to an embodiment.

FIG. 2A is an example of a control resource set with PDCCH candidatesthat may be sent on beam 1 and/or beam 2.

FIG. 2B are examples of CORSETs.

FIG. 3 is an example of different control resource sets that may beassociated with different beams on different OFDM symbols.

FIG. 4 is an example of four CCEs on two OFDM symbols assigned to aPDCCH candidate.

FIG. 5 is an example of distributing CCEs over multiple/different beams(e.g., on first and second OFDM symbols).

FIG. 6 is an example of frequency-first CCE-to candidate mapping forPDCCH.

FIG. 7 is an example of time-first REG-to-CCE mapping when (e.g., all)OFDM symbols of a control region may be associated with a (e.g., one)beam and a (e.g., one) control resource set.

FIG. 8 is an example of distributed frequency-first mapping of REGs toCCEs.

FIG. 8A shows examples of interleaving of frequency-first REG bundles ina multi-symbol CORESET using per-symbol interleaving and across-symbolinterleaving.

FIG. 9 is an example of cross beam scheduling.

FIG. 10 is an example of a frame structure with cross beam scheduling.

FIG. 11 is an example of cross-panel scheduling with four panels.

FIG. 12 is an example of cross TRP scheduling with two TRPs.

FIG. 13 is an example of cross TRP scheduling with decoupleduplink/downlink.

DETAILED DESCRIPTION

A detailed description of illustrative embodiments will now be describedwith reference to the various Figures. Although this descriptionprovides a detailed example of possible implementations, it should benoted that the details are intended to be exemplary and in no way limitthe scope of the application.

FIG. 1A is a diagram illustrating an example communications system 100in which one or more disclosed embodiments may be implemented. Thecommunications system 100 may be a multiple access system that providescontent, such as voice, data, video, messaging, broadcast, etc., tomultiple wireless users. The communications system 100 may enablemultiple wireless users to access such content through the sharing ofsystem resources, including wireless bandwidth. For example, thecommunications systems 100 may employ one or more channel accessmethods, such as code division multiple access (CDMA), time divisionmultiple access (TDMA), frequency division multiple access (FDMA),orthogonal FDMA (OFDMA), single-carrier FDMA (SC-FDMA), zero-tailunique-word DFT-Spread OFDM (ZT UW DTS-s OFDM), unique word OFDM(UW-OFDM), resource block-filtered OFDM, filter bank multicarrier(FBMC), and the like.

As shown in FIG. 1A, the communications system 100 may include wirelesstransmit/receive units (WTRUs) 102 a, 102 b, 102 c, 102 d, a RAN104/113, a CN 106/115, a public switched telephone network (PSTN) 108,the Internet 110, and other networks 112, though it will be appreciatedthat the disclosed embodiments contemplate any number of WTRUs, basestations, networks, and/or network elements. Each of the WTRUs 102 a,102 b, 102 c, 102 d may be any type of device configured to operateand/or communicate in a wireless environment. By way of example, theWTRUs 102 a, 102 b, 102 c, 102 d, any of which may be referred to as a“station” and/or a “STA”, may be configured to transmit and/or receivewireless signals and may include a user equipment (UE), a mobilestation, a fixed or mobile subscriber unit, a subscription-based unit, apager, a cellular telephone, a personal digital assistant (PDA), asmartphone, a laptop, a netbook, a personal computer, a wireless sensor,a hotspot or Mi-Fi device, an Internet of Things (IoT) device, a watchor other wearable, a head-mounted display (HMD), a vehicle, a drone, amedical device and applications (e.g., remote surgery), an industrialdevice and applications (e.g., a robot and/or other wireless devicesoperating in an industrial and/or an automated processing chaincontexts), a consumer electronics device, a device operating oncommercial and/or industrial wireless networks, and the like. Any of theWTRUs 102 a, 102 b, 102 c and 102 d may be interchangeably referred toas a UE.

The communications systems 100 may also include a base station 114 aand/or a base station 114 b. Each of the base stations 114 a, 114 b maybe any type of device configured to wirelessly interface with at leastone of the WTRUs 102 a, 102 b, 102 c, 102 d to facilitate access to oneor more communication networks, such as the CN 106/115, the Internet110, and/or the other networks 112. By way of example, the base stations114 a, 114 b may be a base transceiver station (BTS), a Node-B, an eNodeB, a Home Node B, a Home eNode B, a gNB, a NR NodeB, a site controller,an access point (AP), a wireless router, and the like. While the basestations 114 a, 114 b are each depicted as a single element, it will beappreciated that the base stations 114 a, 114 b may include any numberof interconnected base stations and/or network elements.

The base station 114 a may be part of the RAN 104/113, which may alsoinclude other base stations and/or network elements (not shown), such asa base station controller (BSC), a radio network controller (RNC), relaynodes, etc. The base station 114 a and/or the base station 114 b may beconfigured to transmit and/or receive wireless signals on one or morecarrier frequencies, which may be referred to as a cell (not shown).These frequencies may be in licensed spectrum, unlicensed spectrum, or acombination of licensed and unlicensed spectrum. A cell may providecoverage for a wireless service to a specific geographical area that maybe relatively fixed or that may change over time. The cell may furtherbe divided into cell sectors. For example, the cell associated with thebase station 114 a may be divided into three sectors. Thus, in oneembodiment, the base station 114 a may include three transceivers, i.e.,one for each sector of the cell. In an embodiment, the base station 114a may employ multiple-input multiple output (MIMO) technology and mayutilize multiple transceivers for each sector of the cell. For example,beamforming may be used to transmit and/or receive signals in desiredspatial directions.

The base stations 114 a, 114 b may communicate with one or more of theWTRUs 102 a, 102 b, 102 c, 102 d over an air interface 116, which may beany suitable wireless communication link (e.g., radio frequency (RF),microwave, centimeter wave, micrometer wave, infrared (IR), ultraviolet(UV), visible light, etc.). The air interface 116 may be establishedusing any suitable radio access technology (RAT).

More specifically, as noted above, the communications system 100 may bea multiple access system and may employ one or more channel accessschemes, such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, and the like. Forexample, the base station 114 a in the RAN 104/113 and the WTRUs 102 a,102 b, 102 c may implement a radio technology such as Universal MobileTelecommunications System (UMTS) Terrestrial Radio Access (UTRA), whichmay establish the air interface 115/116/117 using wideband CDMA (WCDMA).WCDMA may include communication protocols such as High-Speed PacketAccess (HSPA) and/or Evolved HSPA (HSPA+). HSPA may include High-SpeedDownlink (DL) Packet Access (HSDPA) and/or High-Speed UL Packet Access(HSUPA).

In an embodiment, the base station 114 a and the WTRUs 102 a, 102 b, 102c may implement a radio technology such as Evolved UMTS TerrestrialRadio Access (E-UTRA), which may establish the air interface 116 usingLong Term Evolution (LTE) and/or LTE-Advanced (LTE-A) and/orLTE-Advanced Pro (LTE-A Pro).

In an embodiment, the base station 114 a and the WTRUs 102 a, 102 b, 102c may implement a radio technology such as NR Radio Access, which mayestablish the air interface 116 using New Radio (NR).

In an embodiment, the base station 114 a and the WTRUs 102 a, 102 b, 102c may implement multiple radio access technologies. For example, thebase station 114 a and the WTRUs 102 a, 102 b, 102 c may implement LTEradio access and NR radio access together, for instance using dualconnectivity (DC) principles. Thus, the air interface utilized by WTRUs102 a, 102 b, 102 c may be characterized by multiple types of radioaccess technologies and/or transmissions sent to/from multiple types ofbase stations (e.g., a eNB and a gNB).

In other embodiments, the base station 114 a and the WTRUs 102 a, 102 b,102 c may implement radio technologies such as IEEE 802.11 (i.e.,Wireless Fidelity (WiFi), IEEE 802.16 (i.e., Worldwide Interoperabilityfor Microwave Access (WiMAX)), CDMA2000, CDMA2000 1X, CDMA2000 EV-DO,Interim Standard 2000 (IS-2000), Interim Standard 95 (IS-95), InterimStandard 856 (IS-856), Global System for Mobile communications (GSM),Enhanced Data rates for GSM Evolution (EDGE), GSM EDGE (GERAN), and thelike.

The base station 114 b in FIG. 1A may be a wireless router, Home Node B,Home eNode B, or access point, for example, and may utilize any suitableRAT for facilitating wireless connectivity in a localized area, such asa place of business, a home, a vehicle, a campus, an industrialfacility, an air corridor (e.g., for use by drones), a roadway, and thelike. In one embodiment, the base station 114 b and the WTRUs 102 c, 102d may implement a radio technology such as IEEE 802.11 to establish awireless local area network (WLAN). In an embodiment, the base station114 b and the WTRUs 102 c, 102 d may implement a radio technology suchas IEEE 802.15 to establish a wireless personal area network (WPAN). Inyet another embodiment, the base station 114 b and the WTRUs 102 c, 102d may utilize a cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE,LTE-A, LTE-A Pro, NR etc.) to establish a picocell or femtocell. Asshown in FIG. 1A, the base station 114 b may have a direct connection tothe Internet 110. Thus, the base station 114 b may not be required toaccess the Internet 110 via the CN 106/115.

The RAN 104/113 may be in communication with the CN 106/115, which maybe any type of network configured to provide voice, data, applications,and/or voice over internet protocol (VoIP) services to one or more ofthe WTRUs 102 a, 102 b, 102 c, 102 d. The data may have varying qualityof service (QoS) requirements, such as differing throughputrequirements, latency requirements, error tolerance requirements,reliability requirements, data throughput requirements, mobilityrequirements, and the like. The CN 106/115 may provide call control,billing services, mobile location-based services, pre-paid calling,Internet connectivity, video distribution, etc., and/or performhigh-level security functions, such as user authentication. Although notshown in FIG. 1A, it will be appreciated that the RAN 104/113 and/or theCN 106/115 may be in direct or indirect communication with other RANsthat employ the same RAT as the RAN 104/113 or a different RAT. Forexample, in addition to being connected to the RAN 104/113, which may beutilizing a NR radio technology, the CN 106/115 may also be incommunication with another RAN (not shown) employing a GSM, UMTS, CDMA2000, WiMAX, E-UTRA, or WiFi radio technology.

The CN 106/115 may also serve as a gateway for the WTRUs 102 a, 102 b,102 c, 102 d to access the PSTN 108, the Internet 110, and/or the othernetworks 112. The PSTN 108 may include circuit-switched telephonenetworks that provide plain old telephone service (POTS). The Internet110 may include a global system of interconnected computer networks anddevices that use common communication protocols, such as thetransmission control protocol (TCP), user datagram protocol (UDP) and/orthe internet protocol (IP) in the TCP/IP internet protocol suite. Thenetworks 112 may include wired and/or wireless communications networksowned and/or operated by other service providers. For example, thenetworks 112 may include another CN connected to one or more RANs, whichmay employ the same RAT as the RAN 104/113 or a different RAT.

Some or all of the WTRUs 102 a, 102 b, 102 c, 102 d in thecommunications system 100 may include multi-mode capabilities (e.g., theWTRUs 102 a, 102 b, 102 c, 102 d may include multiple transceivers forcommunicating with different wireless networks over different wirelesslinks). For example, the WTRU 102 c shown in FIG. 1A may be configuredto communicate with the base station 114 a, which may employ acellular-based radio technology, and with the base station 114 b, whichmay employ an IEEE 802 radio technology.

FIG. 1B is a system diagram illustrating an example WTRU 102. As shownin FIG. 1B, the WTRU 102 may include a processor 118, a transceiver 120,a transmit/receive element 122, a speaker/microphone 124, a keypad 126,a display/touchpad 128, non-removable memory 130, removable memory 132,a power source 134, a global positioning system (GPS) chipset 136,and/or other peripherals 138, among others. It will be appreciated thatthe WTRU 102 may include any sub-combination of the foregoing elementswhile remaining consistent with an embodiment.

The processor 118 may be a general purpose processor, a special purposeprocessor, a conventional processor, a digital signal processor (DSP), aplurality of microprocessors, one or more microprocessors in associationwith a DSP core, a controller, a microcontroller, Application SpecificIntegrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs)circuits, any other type of integrated circuit (IC), a state machine,and the like. The processor 118 may perform signal coding, dataprocessing, power control, input/output processing, and/or any otherfunctionality that enables the WTRU 102 to operate in a wirelessenvironment. The processor 118 may be coupled to the transceiver 120,which may be coupled to the transmit/receive element 122. While FIG. 1Bdepicts the processor 118 and the transceiver 120 as separatecomponents, it will be appreciated that the processor 118 and thetransceiver 120 may be integrated together in an electronic package orchip.

The transmit/receive element 122 may be configured to transmit signalsto, or receive signals from, a base station (e.g., the base station 114a) over the air interface 116. For example, in one embodiment, thetransmit/receive element 122 may be an antenna configured to transmitand/or receive RF signals. In an embodiment, the transmit/receiveelement 122 may be an emitter/detector configured to transmit and/orreceive IR, UV, or visible light signals, for example. In yet anotherembodiment, the transmit/receive element 122 may be configured totransmit and/or receive both RF and light signals. It will beappreciated that the transmit/receive element 122 may be configured totransmit and/or receive any combination of wireless signals.

Although the transmit/receive element 122 is depicted in FIG. 1B as asingle element, the WTRU 102 may include any number of transmit/receiveelements 122. More specifically, the WTRU 102 may employ M IMOtechnology. Thus, in one embodiment, the WTRU 102 may include two ormore transmit/receive elements 122 (e.g., multiple antennas) fortransmitting and receiving wireless signals over the air interface 116.

The transceiver 120 may be configured to modulate the signals that areto be transmitted by the transmit/receive element 122 and to demodulatethe signals that are received by the transmit/receive element 122. Asnoted above, the WTRU 102 may have multi-mode capabilities. Thus, thetransceiver 120 may include multiple transceivers for enabling the WTRU102 to communicate via multiple RATs, such as NR and IEEE 802.11, forexample.

The processor 118 of the WTRU 102 may be coupled to, and may receiveuser input data from, the speaker/microphone 124, the keypad 126, and/orthe display/touchpad 128 (e.g., a liquid crystal display (LCD) displayunit or organic light-emitting diode (OLED) display unit). The processor118 may also output user data to the speaker/microphone 124, the keypad126, and/or the display/touchpad 128. In addition, the processor 118 mayaccess information from, and store data in, any type of suitable memory,such as the non-removable memory 130 and/or the removable memory 132.The non-removable memory 130 may include random-access memory (RAM),read-only memory (ROM), a hard disk, or any other type of memory storagedevice. The removable memory 132 may include a subscriber identitymodule (SIM) card, a memory stick, a secure digital (SD) memory card,and the like. In other embodiments, the processor 118 may accessinformation from, and store data in, memory that is not physicallylocated on the WTRU 102, such as on a server or a home computer (notshown).

The processor 118 may receive power from the power source 134, and maybe configured to distribute and/or control the power to the othercomponents in the WTRU 102. The power source 134 may be any suitabledevice for powering the WTRU 102. For example, the power source 134 mayinclude one or more dry cell batteries (e.g., nickel-cadmium (NiCd),nickel-zinc (NiZn), nickel metal hydride (NiMH), lithium-ion (Li-ion),etc.), solar cells, fuel cells, and the like.

The processor 118 may also be coupled to the GPS chipset 136, which maybe configured to provide location information (e.g., longitude andlatitude) regarding the current location of the WTRU 102. In additionto, or in lieu of, the information from the GPS chipset 136, the WTRU102 may receive location information over the air interface 116 from abase station (e.g., base stations 114 a, 114 b) and/or determine itslocation based on the timing of the signals being received from two ormore nearby base stations. It will be appreciated that the WTRU 102 mayacquire location information by way of any suitablelocation-determination method while remaining consistent with anembodiment.

The processor 118 may further be coupled to other peripherals 138, whichmay include one or more software and/or hardware modules that provideadditional features, functionality and/or wired or wirelessconnectivity. For example, the peripherals 138 may include anaccelerometer, an e-compass, a satellite transceiver, a digital camera(for photographs and/or video), a universal serial bus (USB) port, avibration device, a television transceiver, a hands free headset, aBluetooth® module, a frequency modulated (FM) radio unit, a digitalmusic player, a media player, a video game player module, an Internetbrowser, a Virtual Reality and/or Augmented Reality (VR/AR) device, anactivity tracker, and the like. The peripherals 138 may include one ormore sensors, the sensors may be one or more of a gyroscope, anaccelerometer, a hall effect sensor, a magnetometer, an orientationsensor, a proximity sensor, a temperature sensor, a time sensor; ageolocation sensor; an altimeter, a light sensor, a touch sensor, amagnetometer, a barometer, a gesture sensor, a biometric sensor, and/ora humidity sensor.

The WTRU 102 may include a full duplex radio for which transmission andreception of some or all of the signals (e.g., associated withparticular subframes for both the UL (e.g., for transmission) anddownlink (e.g., for reception) may be concurrent and/or simultaneous.The full duplex radio may include an interference management unit 139 toreduce and or substantially eliminate self-interference via eitherhardware (e.g., a choke) or signal processing via a processor (e.g., aseparate processor (not shown) or via processor 118). In an embodiment,the WRTU 102 may include a half-duplex radio for which transmission andreception of some or all of the signals (e.g., associated withparticular subframes for either the UL (e.g., for transmission) or thedownlink (e.g., for reception)).

FIG. 1C is a system diagram illustrating the RAN 104 and the CN 106according to an embodiment. As noted above, the RAN 104 may employ anE-UTRA radio technology to communicate with the WTRUs 102 a, 102 b, 102c over the air interface 116. The RAN 104 may also be in communicationwith the CN 106.

The RAN 104 may include eNode-Bs 160 a, 160 b, 160 c, though it will beappreciated that the RAN 104 may include any number of eNode-Bs whileremaining consistent with an embodiment. The eNode-Bs 160 a, 160 b, 160c may each include one or more transceivers for communicating with theWTRUs 102 a, 102 b, 102 c over the air interface 116. In one embodiment,the eNode-Bs 160 a, 160 b, 160 c may implement MIMO technology. Thus,the eNode-B 160 a, for example, may use multiple antennas to transmitwireless signals to, and/or receive wireless signals from, the WTRU 102a.

Each of the eNode-Bs 160 a, 160 b, 160 c may be associated with aparticular cell (not shown) and may be configured to handle radioresource management decisions, handover decisions, scheduling of usersin the UL and/or DL, and the like. As shown in FIG. 1C, the eNode-Bs 160a, 160 b, 160 c may communicate with one another over an X2 interface.

The CN 106 shown in FIG. 1C may include a mobility management entity(MME) 162, a serving gateway (SGW) 164, and a packet data network (PDN)gateway (or PGW) 166. While each of the foregoing elements are depictedas part of the CN 106, it will be appreciated that any of these elementsmay be owned and/or operated by an entity other than the CN operator.

The MME 162 may be connected to each of the eNode-Bs 162 a, 162 b, 162 cin the RAN 104 via an S1 interface and may serve as a control node. Forexample, the MME 162 may be responsible for authenticating users of theWTRUs 102 a, 102 b, 102 c, bearer activation/deactivation, selecting aparticular serving gateway during an initial attach of the WTRUs 102 a,102 b, 102 c, and the like. The MME 162 may provide a control planefunction for switching between the RAN 104 and other RANs (not shown)that employ other radio technologies, such as GSM and/or WCDMA.

The SGW 164 may be connected to each of the eNode Bs 160 a, 160 b, 160 cin the RAN 104 via the S1 interface. The SGW 164 may generally route andforward user data packets to/from the WTRUs 102 a, 102 b, 102 c. The SGW164 may perform other functions, such as anchoring user planes duringinter-eNode B handovers, triggering paging when DL data is available forthe WTRUs 102 a, 102 b, 102 c, managing and storing contexts of theWTRUs 102 a, 102 b, 102 c, and the like.

The SGW 164 may be connected to the PGW 166, which may provide the WTRUs102 a, 102 b, 102 c with access to packet-switched networks, such as theInternet 110, to facilitate communications between the WTRUs 102 a, 102b, 102 c and IP-enabled devices.

The CN 106 may facilitate communications with other networks. Forexample, the CN 106 may provide the WTRUs 102 a, 102 b, 102 c withaccess to circuit-switched networks, such as the PSTN 108, to facilitatecommunications between the WTRUs 102 a, 102 b, 102 c and traditionalland-line communications devices. For example, the CN 106 may include,or may communicate with, an IP gateway (e.g., an IP multimedia subsystem(IMS) server) that serves as an interface between the CN 106 and thePSTN 108. In addition, the CN 106 may provide the WTRUs 102 a, 102 b,102 c with access to the other networks 112, which may include otherwired and/or wireless networks that are owned and/or operated by otherservice providers.

Although the WTRU is described in FIGS. 1A-1D as a wireless terminal, itis contemplated that in certain representative embodiments that such aterminal may use (e.g., temporarily or permanently) wired communicationinterfaces with the communication network.

In representative embodiments, the other network 112 may be a WLAN.

A WLAN in Infrastructure Basic Service Set (BSS) mode may have an AccessPoint (AP) for the BSS and one or more stations (STAs) associated withthe AP. The AP may have an access or an interface to a DistributionSystem (DS) or another type of wired/wireless network that carriestraffic in to and/or out of the BSS. Traffic to STAs that originatesfrom outside the BSS may arrive through the AP and may be delivered tothe STAs. Traffic originating from STAs to destinations outside the BSSmay be sent to the AP to be delivered to respective destinations.Traffic between STAs within the BSS may be sent through the AP, forexample, where the source STA may send traffic to the AP and the AP maydeliver the traffic to the destination STA. The traffic between STAswithin a BSS may be considered and/or referred to as peer-to-peertraffic. The peer-to-peer traffic may be sent between (e.g., directlybetween) the source and destination STAs with a direct link setup (DLS).In certain representative embodiments, the DLS may use an 802.11e DLS oran 802.11z tunneled DLS (TDLS). A WLAN using an Independent BSS (IBSS)mode may not have an AP, and the STAs (e.g., all of the STAs) within orusing the IBSS may communicate directly with each other. The IBSS modeof communication may sometimes be referred to herein as an “ad-hoc” modeof communication.

When using the 802.11ac infrastructure mode of operation or a similarmode of operations, the AP may transmit a beacon on a fixed channel,such as a primary channel. The primary channel may be a fixed width(e.g., 20 MHz wide bandwidth) or a dynamically set width via signaling.The primary channel may be the operating channel of the BSS and may beused by the STAs to establish a connection with the AP. In certainrepresentative embodiments, Carrier Sense Multiple Access with CollisionAvoidance (CSMA/CA) may be implemented, for example in in 802.11systems. For CSMA/CA, the STAs (e.g., every STA), including the AP, maysense the primary channel. If the primary channel is sensed/detectedand/or determined to be busy by a particular STA, the particular STA mayback off. One STA (e.g., only one station) may transmit at any giventime in a given BSS.

High Throughput (HT) STAs may use a 40 MHz wide channel forcommunication, for example, via a combination of the primary 20 MHzchannel with an adjacent or nonadjacent 20 MHz channel to form a 40 MHzwide channel.

Very High Throughput (VHT) STAs may support 20MHz, 40 MHz, 80 MHz,and/or 160 MHz wide channels. The 40 MHz, and/or 80 MHz, channels may beformed by combining contiguous 20 MHz channels. A 160 MHz channel may beformed by combining 8 contiguous 20 MHz channels, or by combining twonon-contiguous 80 MHz channels, which may be referred to as an 80+80configuration. For the 80+80 configuration, the data, after channelencoding, may be passed through a segment parser that may divide thedata into two streams. Inverse Fast Fourier Transform (IFFT) processing,and time domain processing, may be done on each stream separately. Thestreams may be mapped on to the two 80 MHz channels, and the data may betransmitted by a transmitting STA. At the receiver of the receiving STA,the above described operation for the 80+80 configuration may bereversed, and the combined data may be sent to the Medium Access Control(MAC).

Sub 1 GHz modes of operation are supported by 802.11af and 802.11ah. Thechannel operating bandwidths, and carriers, are reduced in 802.11af and802.11ah relative to those used in 802.11n, and 802.11ac. 802.11afsupports 5 MHz, 10 MHz and 20 MHz bandwidths in the TV White Space(TVWS) spectrum, and 802.11ah supports 1 MHz, 2 MHz, 4 MHz, 8 MHz, and16 MHz bandwidths using non-TVWS spectrum. According to a representativeembodiment, 802.11ah may support Meter Type Control/Machine-TypeCommunications, such as MTC devices in a macro coverage area. MTCdevices may have certain capabilities, for example, limited capabilitiesincluding support for (e.g., only support for) certain and/or limitedbandwidths. The MTC devices may include a battery with a battery lifeabove a threshold (e.g., to maintain a very long battery life).

WLAN systems, which may support multiple channels, and channelbandwidths, such as 802.11n, 802.11ac, 802.11af, and 802.11ah, include achannel which may be designated as the primary channel. The primarychannel may have a bandwidth equal to the largest common operatingbandwidth supported by all STAs in the BSS. The bandwidth of the primarychannel may be set and/or limited by a STA, from among all STAs inoperating in a BSS, which supports the smallest bandwidth operatingmode. In the example of 802.11ah, the primary channel may be 1 MHz widefor STAs (e.g., MTC type devices) that support (e.g., only support) a 1MHz mode, even if the AP, and other STAs in the BSS support 2 MHz, 4MHz, 8 MHz, 16 MHz, and/or other channel bandwidth operating modes.Carrier sensing and/or Network Allocation Vector (NAV) settings maydepend on the status of the primary channel. If the primary channel isbusy, for example, due to a STA (which supports only a 1 MHz operatingmode), transmitting to the AP, the entire available frequency bands maybe considered busy even though a majority of the frequency bands remainsidle and may be available.

In the United States, the available frequency bands, which may be usedby 802.11ah, are from 902 MHz to 928 MHz. In Korea, the availablefrequency bands are from 917.5 MHz to 923.5 MHz. In Japan, the availablefrequency bands are from 916.5 MHz to 927.5 MHz. The total bandwidthavailable for 802.11ah is 6 MHz to 26 MHz depending on the country code.

FIG. 1D is a system diagram illustrating the RAN 113 and the CN 115according to an embodiment. As noted above, the RAN 113 may employ an NRradio technology to communicate with the WTRUs 102 a, 102 b, 102 c overthe air interface 116. The RAN 113 may also be in communication with theCN 115.

The RAN 113 may include gNBs 180 a, 180 b, 180 c, though it will beappreciated that the RAN 113 may include any number of gNBs whileremaining consistent with an embodiment. The gNBs 180 a, 180 b, 180 cmay each include one or more transceivers for communicating with theWTRUs 102 a, 102 b, 102 c over the air interface 116. In one embodiment,the gNBs 180 a, 180 b, 180 c may implement MIMO technology. For example,gNBs 180 a, 108 b may utilize beamforming to transmit signals to and/orreceive signals from the gNBs 180 a, 180 b, 180 c. Thus, the gNB 180 a,for example, may use multiple antennas to transmit wireless signals to,and/or receive wireless signals from, the WTRU 102 a. In an embodiment,the gNBs 180 a, 180 b, 180 c may implement carrier aggregationtechnology. For example, the gNB 180 a may transmit multiple componentcarriers to the WTRU 102 a (not shown). A subset of these componentcarriers may be on unlicensed spectrum while the remaining componentcarriers may be on licensed spectrum. In an embodiment, the gNBs 180 a,180 b, 180 c may implement Coordinated Multi-Point (CoMP) technology.For example, WTRU 102 a may receive coordinated transmissions from gNB180 a and gNB 180 b (and/or gNB 180 c).

The WTRUs 102 a, 102 b, 102 c may communicate with gNBs 180 a, 180 b,180 c using transmissions associated with a scalable numerology. Forexample, the OFDM symbol spacing and/or OFDM subcarrier spacing may varyfor different transmissions, different cells, and/or different portionsof the wireless transmission spectrum. The WTRUs 102 a, 102 b, 102 c maycommunicate with gNBs 180 a, 180 b, 180 c using subframe or transmissiontime intervals (TTIs) of various or scalable lengths (e.g., containingvarying number of OFDM symbols and/or lasting varying lengths ofabsolute time).

The gNBs 180 a, 180 b, 180 c may be configured to communicate with theWTRUs 102 a, 102 b, 102 c in a standalone configuration and/or anon-standalone configuration. In the standalone configuration, WTRUs 102a, 102 b, 102 c may communicate with gNBs 180 a, 180 b, 180 c withoutalso accessing other RANs (e.g., such as eNode-Bs 160 a, 160 b, 160 c).In the standalone configuration, WTRUs 102 a, 102 b, 102 c may utilizeone or more of gNBs 180 a, 180 b, 180 c as a mobility anchor point. Inthe standalone configuration, WTRUs 102 a, 102 b, 102 c may communicatewith gNBs 180 a, 180 b, 180 c using signals in an unlicensed band. In anon-standalone configuration WTRUs 102 a, 102 b, 102 c may communicatewith/connect to gNBs 180 a, 180 b, 180 c while also communicatingwith/connecting to another RAN such as eNode-Bs 160 a, 160 b, 160 c. Forexample, WTRUs 102 a, 102 b, 102 c may implement DC principles tocommunicate with one or more gNBs 180 a, 180 b, 180 c and one or moreeNode-Bs 160 a, 160 b, 160 c substantially simultaneously. In thenon-standalone configuration, eNode-Bs 160 a, 160 b, 160 c may serve asa mobility anchor for WTRUs 102 a, 102 b, 102 c and gNBs 180 a, 180 b,180 c may provide additional coverage and/or throughput for servicingWTRUs 102 a, 102 b, 102 c.

Each of the gNBs 180 a, 180 b, 180 c may be associated with a particularcell (not shown) and may be configured to handle radio resourcemanagement decisions, handover decisions, scheduling of users in the ULand/or DL, support of network slicing, dual connectivity, interworkingbetween NR and E-UTRA, routing of user plane data towards User PlaneFunction (UPF) 184 a, 184 b, routing of control plane informationtowards Access and Mobility Management Function (AMF) 182 a, 182 b andthe like. As shown in FIG. 1D, the gNBs 180 a, 180 b, 180 c maycommunicate with one another over an Xn interface.

The CN 115 shown in FIG. 1D may include at least one AMF 182 a, 182 b,at least one UPF 184 a,184 b, at least one Session Management Function(SMF) 183 a, 183 b, and possibly a Data Network (DN) 185 a, 185 b. Whileeach of the foregoing elements are depicted as part of the CN 115, itwill be appreciated that any of these elements may be owned and/oroperated by an entity other than the CN operator.

The AMF 182 a, 182 b may be connected to one or more of the gNBs 180 a,180 b, 180 c in the RAN 113 via an N2 interface and may serve as acontrol node. For example, the AMF 182 a, 182 b may be responsible forauthenticating users of the WTRUs 102 a, 102 b, 102 c, support fornetwork slicing (e.g., handling of different PDU sessions with differentrequirements), selecting a particular SMF 183 a, 183 b, management ofthe registration area, termination of NAS signaling, mobilitymanagement, and the like. Network slicing may be used by the AMF 182 a,182 b in order to customize CN support for WTRUs 102 a, 102 b, 102 cbased on the types of services being utilized WTRUs 102 a, 102 b, 102 c.For example, different network slices may be established for differentuse cases such as services relying on ultra-reliable low latency (URLLC)access, services relying on enhanced massive mobile broadband (eMBB)access, services for machine type communication (MTC) access, and/or thelike. The AMF 162 may provide a control plane function for switchingbetween the RAN 113 and other RANs (not shown) that employ other radiotechnologies, such as LTE, LTE-A, LTE-A Pro, and/or non-3GPP accesstechnologies such as WiFi.

The SMF 183 a, 183 b may be connected to an AMF 182 a, 182 b in the CN115 via an N11 interface. The SMF 183 a, 183 b may also be connected toa UPF 184 a, 184 b in the CN 115 via an N4 interface. The SMF 183 a, 183b may select and control the UPF 184 a, 184 b and configure the routingof traffic through the UPF 184 a, 184 b. The SMF 183 a, 183 b mayperform other functions, such as managing and allocating UE IP address,managing PDU sessions, controlling policy enforcement and QoS, providingdownlink data notifications, and the like. A PDU session type may beIP-based, non-IP based, Ethernet-based, and the like.

The UPF 184 a, 184 b may be connected to one or more of the gNBs 180 a,180 b, 180 c in the RAN 113 via an N3 interface, which may provide theWTRUs 102 a, 102 b, 102 c with access to packet-switched networks, suchas the Internet 110, to facilitate communications between the WTRUs 102a, 102 b, 102 c and IP-enabled devices. The UPF 184, 184 b may performother functions, such as routing and forwarding packets, enforcing userplane policies, supporting multi-homed PDU sessions, handling user planeQoS, buffering downlink packets, providing mobility anchoring, and thelike.

The CN 115 may facilitate communications with other networks. Forexample, the CN 115 may include, or may communicate with, an IP gateway(e.g., an IP multimedia subsystem (IMS) server) that serves as aninterface between the CN 115 and the PSTN 108. In addition, the CN 115may provide the WTRUs 102 a, 102 b, 102 c with access to the othernetworks 112, which may include other wired and/or wireless networksthat are owned and/or operated by other service providers. In oneembodiment, the WTRUs 102 a, 102 b, 102 c may be connected to a localData Network (DN) 185 a, 185 b through the UPF 184 a, 184 b via the N3interface to the UPF 184 a, 184 b and an N6 interface between the UPF184 a, 184 b and the DN 185 a, 185 b.

In view of FIGS. 1A-1D, and the corresponding description of FIGS.1A-1D, one or more, or all, of the functions described herein withregard to one or more of: WTRU 102 a-d, Base Station 114 a-b, eNode-B160 a-c, MME 162, SGW 164, PGW 166, gNB 180 a-c, AMF 182 a-ab, UPF 184a-b, SMF 183 a-b, DN 185 a-b, and/or any other device(s) describedherein, may be performed by one or more emulation devices (not shown).The emulation devices may be one or more devices configured to emulateone or more, or all, of the functions described herein. For example, theemulation devices may be used to test other devices and/or to simulatenetwork and/or WTRU functions.

The emulation devices may be designed to implement one or more tests ofother devices in a lab environment and/or in an operator networkenvironment. For example, the one or more emulation devices may performthe one or more, or all, functions while being fully or partiallyimplemented and/or deployed as part of a wired and/or wirelesscommunication network in order to test other devices within thecommunication network. The one or more emulation devices may perform theone or more, or all, functions while being temporarilyimplemented/deployed as part of a wired and/or wireless communicationnetwork. The emulation device may be directly coupled to another devicefor purposes of testing and/or may performing testing using over-the-airwireless communications.

The one or more emulation devices may perform the one or more, includingall, functions while not being implemented/deployed as part of a wiredand/or wireless communication network. For example, the emulationdevices may be utilized in a testing scenario in a testing laboratoryand/or a non-deployed (e.g., testing) wired and/or wirelesscommunication network in order to implement testing of one or morecomponents. The one or more emulation devices may be test equipment.Direct RF coupling and/or wireless communications via RF circuitry(e.g., which may include one or more antennas) may be used by theemulation devices to transmit and/or receive data.

5G new radio (NR) may support millimeter-wave communications, e.g.,compared to 4G Long Term Evolution (LTE) support for sub-6 GHzfrequencies. Support for millimeter-wave communication may involve abeam-based (e.g., as opposed to cell-based) implementation for data andcontrol transmission. A Physical Downlink Control Channel (PDCCH) maysupport an LTE downlink control channel. Enhanced PDCCH (EPDCCH) maysupport an LTE Advanced downlink control channel. EDPCCH may divideresources between data and control, e.g., using Frequency DivisionMultiplexing (FDM). Frequency tones assigned for EDPCCH may cover awhole subframe, for example, instead of three or four orthogonalfrequency division multiplexing (OFDM) symbols. PDCCH and EPDCCH may notsupport multi-beam control and data transmission for 5G NR. Systems,methods, and instrumentalities for PDCCH transmission for cell based andmulti-beam based architectures may be provided herein.

PDCCH transmission may be supported for cell-based and multi-beam-basedarchitectures. 5G NR wireless systems may support a wide range offrequencies and WTRUs with different latency and reliabilityrequirements, for example, using 5G beam-based downlink control channel.A cell-based system architecture (e.g., at lower frequencies) maybroadcast a PDCCH to all WTRUs in a cell. A beam-based systemarchitecture (e.g., at higher frequencies) may provide a beam-basedPDCCH to WTRUs covered by the beam. Support may be provided formulti-beam transmission within a transmission/reception point (TRP) orbetween multiple TRPs while (e.g., simultaneously) supporting unifiedoperation for frequency ranges.

A reference symbol may denote a symbol, such as a complex number thatmay be fixed and known, and may be used as a pilot. A reference signalmay be used to denote a time domain signal that may be generated afterprocessing reference symbols. In an example (e.g., for OFDM), referencesymbols may be complex numbers that may be fed into an Inverse DiscreteFourier Transform (IDFT) block. A reference signal may be an output ofthe IDFT block. A resource element (RE) may be an OFDM symbol on asubcarrier. A resource element group (REG) may refer to a group of REsthat may be used as building blocks of a control channel element (CCE),which may be used to assign resource elements to a user. A REG bundlemay comprise REGs that may be adjacent in time or frequency, groupedtogether, and associated with the same precoder. NR-REG, NR-CCE, andNR-PDCCH may be used to refer to REG, CCE, and PDCCH for new radio (NR)in 5G. WTRU and user may be used interchangeably.

Control resource sets may be assigned for multi-beam controltransmission. A control resource set may include several search spaces.A (e.g., each) search space may include several PDCCH candidates. Acontrol resource set may be defined and/or configured in different waysfor a DL control channel that may use beams. A CORESET configuration maybe semi-static and may be done by using BCH or higher layer signaling(e.g., RRC). A CORESET configuration may include information such as thefollowing (or any combination of them): the CORESET size and resources(e.g., time and frequency); type of REG bundling; transmission mode(e.g., distributed, localized, interleaving, and non-interleavingmapping of REG bundles); aggregation level set; DCI format size set; thenumber of PDCCH candidates that a WTRU monitors for each DCI format sizeand each aggregation level (the number can be zero for somecombinations); quasi-co-located (QCL) assumptions; or whether theCORESET is single-beam or multi-beam.

Multiple single-beam CORESETS may be used to assign and/or configured.Multiple single-beam CORESETS may be assigned and/or configured usingcontrol resource sets associated with multiple beams.

FIG. 2A is an example of a control resource set with PDCCH candidatesthat may be sent on beam 1 and/or beam 2.

In an example, a control resource (CORESET) set may cover (e.g., all ora combination of OFDM symbols associated with multiple beams) OFDMsymbols that may be assigned for downlink control. Different beams maybe used on different OFDM symbols (e.g., as shown by example in FIG.2A). In a resource set configuration, REG bundles may be configured asadjacent REGs in frequency. Mapping of REG bundles to CCEs may be in thefrequency-first manner and may be done either with or withoutinterleaving. QCL assumptions for an OFDM symbol of the control resourceset may be included in the CORESET configuration. QCL assumptions mayinclude (e.g., all) QCL parameters (including average gain, averagedelay, doppler shift, delay spread, doppler spread, spatial RXparameters) or a subset of them. A WTRU may receive a subset of QCLparameters, which may be common to (e.g., all) OFDM symbols, and mayreceive (e.g., additional multiple) subsets of the QCL parameterscorresponding to multiple OFDM symbols included in the CORESET.

To configure a control resource set as multi-beam, a multi-beam propertyof the CORESET may be indicated (e.g., explicitly) during configuration(e.g., through PBCH or RRC). For example, the WTRU may assume that thecontrol resource set is in a multi-beam mode of operation (e.g., if theWTRU receives multiple QCL assumptions corresponding to multiple OFDMsymbols). The multi-beam property of the CORESET may be indicated (e.g.,implicitly) based on the configured REG-to-CCE mapping for a CORESETspanning multiple OFDM symbols. For example, a WTRU may assume that thecontrol resource set is in a multi-beam mode of operation (e.g., if theWTRU is configured with the frequency-first REG-to-CCE mapping (orfrequency-first REG bundling). A WTRU may assume that the controlresource set is in a single-beam mode of operation (e.g., the WTRU isconfigured with the time first REG-to-CCE mapping).

By default, no QCL may be assumed by a WTRU (e.g., a CORESET isconfigured as multi-beam and no QCL assumption is indicated in itsconfiguration). A WTRU may assume that the same QCL assumptions as thosefor PBCH and/or sync signal are valid for the CORESET.

A search space may include PDCCH candidates on multiple OFDM symbols ofa control resource set that may be sent over multiple beams. A (e.g.,each) PDCCH candidate may be sent (e.g., only) over a (e.g., one) beam(e.g., on one OFDM symbol). Different PDCCH candidates of a search spacemay be on different OFDM symbols that may be sent over different beams.A (e.g., one) PDCCH candidate may include CCEs on different OFDM symbolsthat may be sent over different beams. CCEs may be configured overmultiple (e.g., two) OFDM symbols and may be sent over two differentbeams. An example of a single-beam CORESET and three multi-beam CORESETSare shown in FIG. 2B. FIG. 2B from left to right shows: (i) single-beamCORESETs with each CORESET associated with a single beam; (ii) amulti-beam CORESET with each PDCCH transmitted on a single beam; (iii) amulti-beam CORESET with each CCE including a multi-beam PDDCHtransmitted on a single beam; and (iv) a multi-beam CORESET withinterleaved REG bundles that include a CCE transmitted on differentbeams.

Control resource sets may be associated with a (e.g., only one) beam(e.g., single beam CORESETs).

FIG. 3 is an example of different control resource sets that may beassociated with different beams on different OFDM symbols.

Different control resource sets may be associated with different beamson different OFDM symbols (e.g., as shown by example in FIG. 3). One ormore (e.g., all) PDCCH candidates of a search space may be associatedwith a (e.g., only one) beam and a (e.g., one) OFDM symbol. One or more(e.g., all) candidates of a search space may be inside a (e.g., one)control resource set. An adjacent control resource set may havedifferent or similar REG-to-CCE and CCE-to-candidate mappings. In anexample, one control resource set may support localized PDCCH and theother control resource set may support distributed PDCCH. One or more(e.g., all) PDCCH candidates of a search space may be associated with a(e.g., only one) beam over one or more OFDM symbols, for example, when abeam may be transmitted over multiple OFDM symbols. A CORESETsingle-beam property may be included as part of the CORESET'sconfiguration, which may provide (e.g., by implying) the QCL assumptionfor the whole CORESET. Indication of time-first REG bundling (e.g., ortime-first REG-to-CCE mapping) in the configuration of the CORESET mayprovide (e.g., implicitly provide) the single-beam property of theCORESET and/or the QCL assumption for the whole CORESET. Single-beam maybe used by default and the single beam REG-to-CCE mapping may befrequency-first (e.g., in the case that a control resource set spansonly one OFDM symbol).

A multi-beam CORESET with a (e.g., each) PDCCH transmitted on a singlebeam may be used. A CORESET may span multiple OFDM symbols that areassociated with multiple beams (e.g., each associated with one or moreOFDM symbol). A PDCCH candidate inside this CORESET may be on one OFDMsymbol and transmitted by one beam. A WTRU may use one QCL assumptionfor PDCCH detection (e.g., which may be associated with the OFDM symbolthat the PDCCH is mapped to). Different PDCCH candidates of aWTRU-specific search space (including the potential PDCCH candidates forthe WTRU) may be associated with different beams. PDCCH candidates(e.g., all candidates) of a search space may be associated with a singlebeam. A search space may be (e.g., dynamically) restricted to a subsetof PDCCH candidates on one beam, based on (e.g., dynamic) signalingthrough group-common PDCCH (e.g., in the case that a WTRU-specificsearch space is associated with multiple beams).

A multi-beam CORESET with (e.g., each) CCE transmitted on a single beammay be used. For a multi-beam CORESET, one PDCCH candidate may includetwo or more CCEs on different OFDM symbols (e.g., where each CCE couldpotentially be transmitted on a different beam). A CCE may be entirelymapped on one OFDM symbol and transmitted by a single beam. A WTRU mayuse multiple sets of QCL assumptions for PDCCH detection with (e.g.,each) CCE associated with the QCL assumption of the corresponding OFDMsymbol that it is mapped to.

A multi-Beam CORESET with interleaved REG bundles including a CCE may betransmitted on different beams. A (e.g., each) REG bundle may be (e.g.,entirely) located on one OFDM symbol and transmitted by a single beam.In the case of interleaving of REG bundles across different OFDM symbolof the CORESET, one CCE may include REG bundles on different OFDMsymbols, transmitted by different beams. The WTRU may include multiplesets of QCL assumptions for PDCCH detection with each REG bundle beingassociated with the QCL assumption of the corresponding OFDM symbol thatit is mapped to.

REG bundling may follow a frequency-first mapping (e.g., for multi-beamCORESET with each PDCCH transmitted on a single beam; multi-beam CORESETwith each CCE including a multi-beam PDCCH transmitted on a single-beam;and multi-beam CORESET with interleaved REG bundles including a CCEtransmitted on a single beam). A WTRU may assume the block ofcomplex-valued symbols (e.g., d(0), . . . , d(M_(symb)−1)) are mapped toresource elements (k l) on antenna port (p) in increasing order of firstk, then, l in the control-channel elements within an OFDM symbol usedfor a given PDCCH (e.g., where k is the frequency index and l is theOFDM symbol index within a subframe).

A (e.g., one) PDCCH may be transmitted with multiple beams. Differentbeams may be used on available OFDM symbols of a control resource set,for example, when a control resource set may be (e.g., is) defined overmultiple OFDM symbols. PDCCH candidates may be formed and sent overmultiple OFDM symbols, for example, using different beams. Beams may betransmitted, for example, by one or more TRPs (e.g., the same TRP ormultiple TRPs). Transmitting a (e.g., one) PDCCH on different beams mayprovide beam diversity and may (e.g., drastically) reduce a probabilityof shadowing and beam blocking.

FIG. 4 is an example of four CCEs on two OFDM symbols assigned to aPDCCH candidate. First and second OFDM symbols may be sent over twodifferent beams. A PDCCH may be sent over multiple beams, for example,by dividing its CCEs among the multiple beams. In an example (e.g., asshown in FIG. 4), a PDCCH with an aggregation level (AL) of four mayhave two CCEs on a first OFDM symbol (e.g., sent over a first beam) andtwo CCEs over a second OFDM symbol (e.g., sent over a second beam).Symbols transmitted over the CCEs of a PDCCH may be, for example,repetitions of each other (e.g., sent using different precoding) or maybe, for example, obtained by modulating the output bits of a commonforward error correcting code (FEC) whose input bits may be downlinkcontrol information (DCI).

FIG. 5 is an example of distributing CCEs over multiple/different beams(e.g. on first and second OFDM symbols). In an example, a PDCCH may besent over multiple beams, for example, by sending a (e.g., each) CCEover multiple beams. In an example, a CCE of size 6 may have 3 REGs on afirst symbol (e.g., sent over a first beam) and 3 REGs over a secondOFDM symbol (e.g. sent over a second beam). Multiple (e.g., two) CCEsmay each consist of multiple (e.g., two) REG bundles of size 3 (e.g.,sent over multiple (two) different beams). This procedure may be useful,for example, to add beam diversity to frequency diversity (e.g., fordistributed PDCCH).

CCEs may be mapped for multi-beam transmission. CCEs may be mapped toPDCCH candidates, for example, by time-first mapping and/orfrequency-first mapping. In an example of frequency-first mapping,consecutive CCEs in frequency (e.g., on the same OFDM symbol) may beassigned to a PDCCH candidate. In an example of time-first mapping,adjacent CCEs in time may be assigned to a PDCCH candidate. RemainingCCEs of a PDCCH candidate may be in another PRB, for example, when anaggregation level may be larger than a time length of a control resourceset.

In an example, a frequency-first CCE-to-candidate mapping may be used,for example, when a control resource set may cover an (e.g., only one)OFDM symbol.

In an example, time-first or frequency-first, CCE-to-candidate mappingsmay be used, for example, when a control resource may cover multipleOFDM symbols.

FIG. 4 is an example of time-first CCE-to candidate mapping.

FIG. 6 is an example of frequency-first CCE-to candidate mapping forPDCCH. Frequency-first CCE-to candidate mapping may be used, forexample, when a (e.g., each) PDCCH may be sent over a (e.g., one) beam.

Time-first and frequency-first mapping may be used, for example, to mapREGs to CCEs. In an example, time-first REG-to-CCE mapping forbeam-based PDCCH transmission may be useful, for example, when (e.g.,all) OFDM symbols of a control region may be associated with a (e.g.,single) beam. A time-first REG-to-CCE mapping may be used (e.g., in thiscase). REGs on the same PRB (e.g., adjacent in time) may be bundledtogether, for example, to improve channel estimation through RSaggregation. In an example, one or more REGs may use a DMRS in adjacentREGs for channel estimation. FIG. 7 presents an example of this.

FIG. 7 is an example of time-first REG-to-CCE mapping when (e.g., all)OFDM symbols of a control region may be associated with a (e.g., one)beam and a (e.g., one) control resource set.

In an example, a (e.g., each) OFDM symbol may be associated with aseparate beam. REGs may be mapped to CCEs, for example, by using afrequency-first mapping. REG bundling may (e.g., also) be performed infrequency. FIG. 8 presents an example of distributed frequency-firstmapping of REGs to CCEs.

FIG. 8 is an example of distributed frequency-first mapping of REGs toCCEs. In an example, REG bundling size may be 3. First and second OFDMsymbols may be associated with multiple (e.g., two) different beams.

Per-symbol interleaving and across-symbol interleaving may be used. FIG.8A is an example of interleaving of frequency-first REG bundles in amulti-symbol CORESET using per-symbol interleaving (e.g., left side ofFIG. 8A) and across-symbol interleaving (e.g., right side of FIG. 8A).

Frequency-first REG bundling may be used in a multi-symbol CORESET.Interleaving of REG bundles inside the CORESET can be done in differentways. The REG bundles may be interleaved on each symbol separately(e.g., as shown in the left side of FIG. 8A) (e.g., per-symbolinterleaving). For example, l.k REG bundles of the CORESET may bepartitioned to l subsets corresponding to l OFDM symbol of the CORESET,each containing k REG bundles. REG bundles in each subset may beinterleaved by an interleaver (e.g., with design parameters that may bepredefined by specification or configured by RRC). Consecutivelyinterleaved REG bundles (e.g., REG bundles that are consecutive in theirinterleaved indices) may be assigned to CCEs. Consecutive CCEs may beassigned to PDCCH candidates. A CCE may be on one OFDM symbol (e.g.,corresponding to one beam). A PDCCH candidate may be on one OFDM symbol(e.g., corresponding to one beam). The design parameters of theinterleavers on different symbols may be the same or different.

The REG bundles may be interleaved across symbols (e.g., as shown inFIG. 8A, on the right-hand side). In such a case (e.g., which may bereferred to as cross-symbol or across-symbol interleaving), l.k REGbundles of the CORESET (e.g., with k REG bundle on each of the l OFDMsymbols of the CORESET) may be interleaved by an interleaver (e.g., withdesign parameters that may be predefined by specification or configuredby RRC). Consecutively interleaved REG bundles (e.g., REG bundles thatare consecutive in their interleaved indices) may be assigned to CCEs.Consecutive CCEs may be assigned to PDCCH candidates. A CCE can be onmultiple OFDM symbols (e.g., corresponding to multiple beams). A PDCCHcandidate can be on multiple OFDM symbols (e.g., corresponding tomultiple beams). This may provide multi-beam diversity for PDCCHtransmission. The estimate of the content of each REG bundle may beobtained based on its corresponding beam and/or its corresponding QCLassumptions (e.g., to realize the multi-beam diversity in reception ofPDCCH). The multi-beam PDCCH detection may be determined by combiningsoft detected contents of REG bundles on different beams, e.g., toachieve beam diversity.

The interleaving mode (e.g., inter-symbol or cross-symbol interleaving)may be predefined in specifications or included in the CORESETconfiguration. For example, one bit in the CORESET configuration, e.g.,by RRC may indicate whether the interleaving is per-symbol orcross-symbol. In examples, an indication of the interleaving mode may bemixed with other parameter configurations of the CORESET. For example, 3bits in CORESET configuration may indicate the choice among casesincluding at least the following: (i) time-first bundling withoutinterleaving; (ii) time-first bundling with interleaving with REG bundlesize equal to the length of CORESET; (iii) time-first bundling withinterleaving with REG bundle size equal to the size of CCE; (iv)frequency-first bundling without interleaving; (v) frequency-firstbundling with per-symbol interleaving; and/or (vi) frequency-firstbundling with cross-symbol interleaving.

Per-symbol interleaving may have a reduction of effective search space.A (e.g., each) PDCCH candidate may be entirely on one OFDM symbol (e.g.,for frequency-first REG bundling with per-symbol interleaving in amulti-symbol CORESET). The PDCCH candidates of a set of a search space(e.g., or a set of search spaces) corresponding to a WTRU may bepartitioned to multiple parts (e.g., each corresponding to one OFDMsymbol of the CORESET and including the PDCCH candidates on thatcorresponding OFDM symbol). The effective search space (e.g., oreffective set of search spaces) of the WTRU may be restricted to one ofthose parts (e.g., only one of those parts). The WTRU may perform blinddecoding of PDCCH (e.g., only) for candidates on a specific OFDM symbolinside the CORESET (e.g., or a subset of OFDM symbols inside theCORESET). The choice of the OFDM symbol of the CORESET for limiting theeffective search space of a WTRU may be based on the proximity of thecorresponding beam to the beam that is used by WTRU for other purposes(e.g., PDSCH). The WTRU may know its corresponding OFDM symbol (e.g.,for the limited effective search space) through signaling from a gNodeB(e.g., explicit information from gNodeB through group-common PDCCHthrough configuration) or without additional signaling from gNodeB. Forexample, the WTRU may identify its corresponding OFDM symbol (e.g., forthe limited effective search space) without signaling from gNodeB, byusing information the WTRU gathers from beam tracking and/or itscorresponding beams for PDSCH.

For implicit identification of the WTRU's corresponding symbol in theCORESET by the WTRU, the WTRU may compare beams corresponding to thesymbols of the CORESET with the beam or beams that the WTRU tracks fromthe SS/PBCH block, where SS refers to the synchronization signals. TheWTRU may implicitly identify its corresponding symbol of the CORESET(e.g., if the beam associated to the symbol coincides to the beam, orone of the beams, associated to the WTRU, or if the beam associated withthe symbol is closer to the beam or beams associated with the WTRU,among the beams associated with the CORESET).

The identification of the corresponding symbol of the CORESET may bedetermined by the WTRU by comparing the beam associated with each symbolof the CORESET to a WTRU-specific set of beams that is configured by RRCor other higher layer signaling for the WTRU.

For comparing the beams associated to symbols of the CORESET with thebeams or the set of beams associate to a WTRU, the WTRU may use channelestimation information from the DMRS. The metric for the comparison ofthe beams associated to symbols of the CORESET with the beams or the setof beams associated to a WTRU may be based on maximizing the channelcorrelation.

A downlink control indicator (DCI) may be provided for multi-dimensionaltransmission with primary and secondary dimensions. Additionaltransmission dimensions, such as beams, beam-pair links, panels, andTRPs, may be defined in NR. In an example, an (e.g., a single) NR-PDSCHmay be assigned per dimension (e.g., for a multiple NR-PDSCHtransmission scenario). In an (e.g., alternative) example, an (e.g., asingle) NR-PDSCH may be jointly transmitted over multiple dimensions(e.g., with diversity transmission).

An NR-PDCCH may be transmitted per dimension, for example, to sendcontrol information for transmission on the dimensions. A system may(e.g., alternatively) send an (e.g., one) NR-PDCCH, for example, toenable cross-dimensional scheduling and to send cross dimensionalcontrol information.

A WTRU may monitor search spaces for a (e.g., each) dimension, forexample, for use of per-dimensional NR-PDCCH.

In an example, an NR-PDCCH for a (e.g., each) dimension may, forexample, be assigned independent (e.g., non-restricted) search spaces.This may increase the complexity of a blind decoding procedure for aWTRU and may provide the most flexibility for resource assignment.

In an example, an NR-PDCCH for a (e.g., each) dimension may, forexample, be assigned a restricted search space that may depend on searchspaces of one or more other dimensions. Restrictions may limit the sizeof a (e.g., an assigned) search space.

In an example, a WTRU may monitor search spaces in a (e.g., one)dimension, for example, when a (e.g., single) NR-PDCCH may be used forcross-dimensional control channel information transmission.

In an example, a (e.g., single) dimension may be designated as a primarydimension. An NR-PDCCH may be sent on a primary dimension and may assignresources on (e.g., all) other (e.g., secondary) dimensions. Selectionof a primary dimension may, for example, depend on a dimension that maycover the WTRUs most reliable dimensions and/or dimensions that may beavailable at a specific time.

In an example in beam-based transmission, a primary beam pair may bebased on a wide beam at a TRP that may cover a set of narrow beams and acorresponding receive beam at WTRUs. One or more secondary beam(s) maybe a set of narrow beams.

FIG. 9 is an example of cross beam scheduling. A DCI in an NR-PDCCH mayinclude an index of a (e.g., specific) dimension that a WTRU may (e.g.,should) use for a time duration of a resource. In an example, NR-PDCCHmay occupy the first two symbols of a slot. A WTRU may (e.g., for thefirst two symbols) switch its beam to a primary beam (e.g., NR-PDCCHbeam) and may (e.g., upon reading an NR-DCI) switch its beam to anindicated or desired receive/transmit beam for other (e.g., the lastfive) symbols of a slot.

FIG. 10 is an example of a frame structure with cross beam scheduling.

In an example, a gNB and WTRUs (e.g., UEs) may (e.g., in slot 1) switchto primary beam pair links (BPLs), e.g., BPL1.

A gNB and WTRUs may (e.g., for the first N OFDM symbols) stay in anantenna configuration and decode a primary PDCCH, where N may beconfigurable.

A PDCCH DCI may inform WTRU1 and WTRU2 about resources that may be usedin a time domain and a frequency domain.

A PDCCH DCI may inform WTRU1 and WTRU2 about a BPL that they may (e.g.,must) use in resources (e.g., BPL2 and BPL4).

WTRUs may switch to resources and antenna configurations (e.g., theremay be a gap period between PDCCH and PDSCH to allow for the switch).

WTRUs may decode their PDSCHs for a remainder of a slot.

A gNB and WTRUs may (e.g., in slot 2) switch back to primary beam pairlinks (e.g., BPL1).

A gNB and WTRUs may (e.g., for the first N OFDM symbols) stay in anantenna configuration and decode a primary PDCCH, where N may beconfigurable and may be different from resources used in slot 1.

A PDCCH DCI may inform WTRU1 and WTRU2 about resources that may be usedin a time domain and a frequency domain and an antenna configuration.Resources may span a (e.g., an entire) frequency domain. WTRUs mayswitch to a downlink MU-MIMO mode.

WTRUs may switch resources and antenna configurations (e.g., there maybe a gap period between PDCCH and PDSCH to allow for the switch).

WTRUs may decode their PDSCHs for the rest of a slot.

A PDCCH (e.g., for primary beams) may (e.g., always) be present.Secondary beams may not contain a PDCCH in connected mode. A secondarybeam PDCCH may be sent at different periodicity for beam management.

Primary beams may be sent from the same or different TRPs, panels, etc.

In an example, a (e.g., the same) NR-PDCCH may be sent on one or more(e.g., all) dimensions (e.g., for redundancy).

Cross dimensional scheduling may be enabled, for example, by defining anindicator for a (e.g., each) dimension, e.g., to enable a WTRU toidentify a dimension. A dimension may be global (e.g., unique over allWTRUs) or may be WTRU specific. This may enable a primary cell toindicate a dimension for specific control information.

A flag may be provided, for example, to inform a WTRU whether controlinformation may be derived from a primary dimension or may be derivedindependently.

DCI information may be structured, for example, to enable an independentDCI for a (e.g., each) dimension (e.g., [DCIx, dimension]).

DCI information may be structured, for example, to enable a dependentDCI for a subset of dimensions (e.g., [DCIx, dimension1,, . . . ,dimension n]).

This framework (e.g., architecture, configuration, and/or procedures)may permit cross-beam scheduling, cross-panel scheduling and cross TRPscheduling.

A search space may provide multi-beam, multi-TRP transmission. Multi-TRPas used herein may include multi-beam (panel).

In a multi-TRP transmission system, as shown for example in FIG. 12, a(e.g., each) TRP may transmit a (e.g., different) NR-PDSCH transmission.However, the scheduling of (e.g., different) NR-PDSCH may be done by asingle PDCCH (e.g., through cross-TRP scheduling). A gNB may schedule adownlink transmission by at least one of the TRPs by transmitting theNR-PDCCH from a (e.g., the main) TRP.

The cross TRP scheduling may be implemented by adding a TRP indicatorfield (TIF) to each DCI format to indicate the related information tothe NR-PDSCH transmission.

A TIF may include bits that represent the index of the TRP to which thePDSCH scheduling corresponds. The primary TRP may send multiple DCIseach with a different TIF to indicate multiple scheduling informationcorresponding to multiple NR-PDSCH payloads. A TIF may include bits thatrepresent the overall number of TRPs that participate in thetransmission. A TIF may be a single bit that indicates the presence ofcross-TRP scheduling.

The cross TRP scheduling can be activated/de-activated dynamically bymonitoring the presence of a TIF in a DCI. A gNB can either enable ordisable the cross-TRP scheduling independently with a higher layer,e.g., RRC or similar signaling.

A WTRU may determine the starting symbol of the NR-PDSCH of each TRPdynamically (e.g., from a starting symbol field (SSF)). A WTRU may beconfigured with a starting symbol field for each TRP.

A common search space may be transmitted by a TRO (e.g., the primaryTRP). The WTRU-specific search spaces may be transmitted by the TRPs(e.g., all the configured TRPs).

A WTRU may monitor the common search space on the primary TRP signal(e.g., to determine if it is configured for multi-TRP transmission, forexample, if a TIF is present). If a WTRU determines that it isconfigured for multi-TRP transmission, then the WTRU may monitor (e.g.,all) the WTRU specific search spaces of the configured TRPs. Forexample, the WTRU may look for DCIs whose CRC are scrambled with anRNTI. The RNTI may be the C-RNTI of the primary TRP that indicates theassociation of the WTRU content to the common control DCI or it may be aTRP-specific RNTI.

A WTRU may have one or more search spaces. A monitoring and detectionprocedure may comprise blind decoding. A (e.g., each) WTRU-specificsearch space may include a number of potential PDCCH candidates that theWTRU may monitor, for example, to find and detect its assigned PDCCH. A(e.g., one) search space may belong (e.g., completely) to a controlresource set. Different search spaces in different control resource setsmay be assigned to a WTRU. In an example, a total number of blinddecodings for a WTRU (e.g., a total number of PDCCH candidates in searchspaces corresponding to the WTRU) may be limited, for example, by afixed number, which may be independent of a number of search spaces andcontrol resource sets. In an (e.g., alternative) example, there may be a(e.g., fixed or configured) maximum number of blind decodings percontrol resource set and/or per beam.

Cross panel scheduling may be provided. An NR TRP may be equipped withmultiple panels. A TRP may transmit (e.g., simultaneously) multipleNR-PDSCHs to a WTRU and it may allocate a (e.g., one) NR-PDSCH perpanel. A (e.g., each) panel may have, for example, its own controlresources with its own DCI that may contain scheduling assignments. ATRP may, for example, send DCIs for multiple panels on a (e.g., single)NR-PDCCH from a primary TRP (e.g., compared to sending an NR-PDCCH perpanel).

FIG. 11 is an example of cross-panel scheduling with four panels. In anexample, a TRP with four panels may send four NR-PDSCHs to a WTRU with a(e.g., only one) NR-PDCCH on the first panel. A resource assignment fora (e.g., each) NR-PDSCH may, for example, be independent. A resourceassignment may be placed in an NR-PDCCH without overlapping with eachother. In an example, a WTRU may decode multiple DCIs. A (e.g., each)DCI may contain different resource assignments for a (e.g., each)NR-PDSCH (e.g., scheduled RBs, MCS).

In an example, a TRP may configure a panel indicator, for example, toset a start of a search space for a (e.g., each) panel, e.g., when crosspanel scheduling may be activated. A TRP may configure search spaces,for example, so that a (e.g., each) panel's DCI may be allocated on itsown region of an NR-PDCCH. A WTRU may (e.g., then) decode its multiplepanel resource assignments from a (e.g., single) panel.

A starting location of CCEs for a search space of a (e.g., each) panelmay be calculated, for example, in accordance with Eq. (1):

$\begin{matrix}{m^{\prime} = {m + {\sum\limits_{x = 0}^{n_{PI} - 1}M_{x}^{(L)}}}} & (1)\end{matrix}$

where m is the NR-PDCCH candidate index, M_(x) ^((L)) may be a number ofNR-PDCCH candidates at aggregation level L and n_(PI) may be a panelindicator (e.g., ranging from 1 to a number of coordinating panels at aP-TRP).

In an example (e.g., with multiple TRPs), panels may not be collocated(e.g., a first panel may be located on a P-TRP and a second panel may belocated on an S-TRP). Coordinating TRPs may perform cross panelscheduling in a similar way. In an example, an NR-PDCCH of a P-TRP maybe used to send a DCI for a P-TRP and an S-TRP. The number of panelsmay, for example, be pooled between coordinating TRPs. A panel indicatormay, for example, range from 1 to a number of combined coordinatingpanels between P-TRP and S-TRP.

Hashing functions may be used to determine the search space locations.

A panel indicator may (e.g., when cross panel scheduling may beactivated) be included in a DCI, for example, to inform a WTRU whichpanel a DCI may correspond to. A TRP may, for example, signal (e.g.,through higher layer signaling such as RRC) a WTRU that cross panelscheduling may be active. Cross panel scheduling may (e.g., dynamically)be indicated to the WTRU by the presence of the panel indicator in theDCI.

Cross TRP scheduling may be provided. Multiple TRPs may coordinate(e.g., similar to multi-panel coordination), for example, so that a(e.g., each) TRP may send its own NR-PDSCH to a WTRU. A WTRU's servingcell may be configured as a primary TRP for a WTRU. A primary TRP mayperform cross TRP scheduling, for example, by sending (e.g., through a,for example, single, NR-PDCCH) one or more (e.g., all) DCIs that may beintended for multiple TRPs.

FIG. 12 is an example of cross TRP scheduling with two TRPs. In anexample, two TRPs may coordinate. A P-TRP may operate as a serving cellto a WTRU. In an example, a (e.g., each) TRP may send its own NR-PDSCHwhile (e.g., only) a P-TRP may send an NR-PDCCH. A P-TRP may (e.g.,also) use cross TRP scheduling, for example, for decoupleddownlink/uplink (e.g., as shown in FIG. 13).

FIG. 13 is an example of cross TRP scheduling with decoupleduplink/downlink. In an example, a WTRU may receive an NR-PDSCH on adownlink from a (e.g., one) cell. A WTRU may send its NR-PUSCH on anuplink, e.g., towards a second TRP. Multiple (e.g., both) TRPs maycoordinate. A P-TRP serving a WTRU on a downlink may send DCIs to theWTRU that may be intended for its own link and for an S-TRP's link. DCIsmay be used, for example, for scheduling assignments and/or for powercontrol commands on an uplink towards a second TRP.

In an (e.g., alternative) example, a TRP may configure a TRP indicatorto set a start of a search space for a (e.g., each) TRP's DCI, forexample, when cross TRP scheduling may be active. A TRP may configuresearch spaces, for example, so that a (e.g., each) TRP's DCI may beallocated on its own region of an NR-PDCCH. A WTRU may (e.g., then)decode its multiple TRP resource assignments from a (e.g., single)panel.

A starting location of CCEs for a search space of a (e.g., each) panelmay be calculated, for example, according to Eq. (2):

$\begin{matrix}{m^{\prime} = {m + {\sum\limits_{x = 0}^{n_{TI} - 1}M_{x}^{(L)}}}} & (2)\end{matrix}$

where m is the NR-PDCCH candidate index, M_(x) ^((L)) may be a number ofNR-PDCCH candidates at aggregation level L and n_(TI) may be a TRPindicator, ranging from 1 to the number of coordinating TRPs.

A TRP indicator may (e.g., when cross TRP scheduling may be active) beincluded in a DCI, for example, to inform a WTRU which TRP a DCI maycorrespond to. A TRP may signal (e.g., through higher layer signalingsuch as RRC) a WTRU that cross TRP scheduling may be active.

Cross TRP scheduling may (e.g., dynamically) be indicated to the WTRU bythe presence of the TRP indicator in the DCI. Multi-layer transmissionand Multi-PDSCH transmission from multiple TRPs may be used. Data may betransmitted from multiple TRPs to a WTRU by for example transmittingmultiple PDSCHs, each from a (e.g., one) TRP and scheduled by itscorresponding PDCCH or by transmitting one PDSCH, scheduled by (e.g.,one) PDCCH, using (e.g., different) layers from different TRPs.

The corresponding layers from different TRPs can be on the same ordifferent time and frequency resources for a PDSCH (e.g., a singlePDSCH, including multiple layers transmitted from multiple TRPs). Layersmay be transmitted on the same time and frequency resources using spacedivision multiple access or simple successive interference cancellation(SIC) (e.g., if they are multiplexed by power-level NOMA). For SIC, thereception may be coherent or non-coherent (e.g., without needingsynchronization)

PDCCH may be provided for URLLC in a beam-based system. A monitoringinterval may be instituted, for example, for URLLC transmission in beambased systems. A gNB may switch to a beam that may have coverage of a(e.g., large) subset of URLLC WTRUs. URLLC WTRUs and a gNB may negotiatea (e.g., the best) receive beam for a transmit beam. A gNB may transmita URLLC control channel, e.g., during an interval.

PDCCH for a URLLC WTRUs may be restricted, for example, to an (e.g.,one) OFDM symbol. A frequency may be restricted. One or morerestrictions may, for example, reduce overhead.

Systems, methods and instrumentalities have been disclosed forbeam-based PDCCH Transmission in NR. Control resource sets may beassigned for multi-beam control transmission. A PDCCH may be transmittedwith multiple beams. CCEs may be mapped for multi-beam transmission. DCImay support multi-dimensional transmission with primary and secondarydimensions. Search space may support multi-beam, multi-TRP transmission.

Features, elements and actions (e.g., processes and instrumentalities)are described by way of non-limiting examples. While examples may bedirected to LTE, LTE-A, New Radio (NR) or 5G protocols, subject matterherein is applicable to other wireless communications, systems, servicesand protocols. Each feature, element, action or other aspect of thedescribed subject matter, whether presented in figures or description,may be implemented alone or in any combination, including with othersubject matter, whether known or unknown, in any order, regardless ofexamples presented herein.

A WTRU may refer to an identity of the physical device, or to the user'sidentity such as subscription related identities, e.g., MSISDN, SIP URI,etc. WTRU may refer to application-based identities, e.g., user namesthat may be used per application.

Each of the computing systems described herein may have one or morecomputer processors having memory that are configured with executableinstructions or hardware for accomplishing the functions describedherein including determining the parameters described herein and sendingand receiving messages between entities (e.g., WTRU and network) toaccomplish the described functions. The processes described above may beimplemented in a computer program, software, and/or firmwareincorporated in a computer-readable medium for execution by a computerand/or processor.

The processes described above may be implemented in a computer program,software, and/or firmware incorporated in a computer-readable medium forexecution by a computer and/or processor. Examples of computer-readablemedia include, but are not limited to, electronic signals (transmittedover wired and/or wireless connections) and/or computer-readable storagemedia. Examples of computer-readable storage media include, but are notlimited to, a read only memory (ROM), a random access memory (RAM), aregister, cache memory, semiconductor memory devices, magnetic mediasuch as, but not limited to, internal hard disks and removable disks,magneto-optical media, and/or optical media such as CD-ROM disks, and/ordigital versatile disks (DVDs). A processor in association with softwaremay be used to implement a radio frequency transceiver for use in aWTRU, terminal, base station, RNC, and/or any host computer.

1. A method associated with a wireless transmit/receive unit (WTRU), themethod comprising: receiving a PDCCH transmission, from a wirelesscommunication system, that comprises a control resource set (CORESET)configuration comprising a resource group (REG) bundle; determining, atthe WTRU, whether the REG bundle is interleaved within symbols or acrosssymbols; detecting, at the WTRU, the REG bundle using a beamcorresponding to the REG bundle, if the WTRU determined that the REGbundle is interleaved across symbols; and determining, at the WTRU, amultibeam PDCCH using the detected REG bundle and multiple beamsassociated with the PDCCH transmission.
 2. The method of claim 1,further comprising determining, at the WTRU, that the REG bundle isbundled in frequency, and determining at the WTRU that the PDCCHtransmission is a multibeam transmission based on the determination thatthe REG bundle is bundled in frequency.
 3. The method of claim 1,wherein detecting the REG bundle further comprises detecting, at theWTRU, the REG bundle using the beam corresponding to the REG bundle andquasi collocated (QCL) information for the REG bundle, if the WTRUdetermined that the REG bundle is interleaved across symbols.
 4. Themethod of claim 1, further comprising, determining, at the WTRU, thatthe received PDCCH transmission is a multibeam transmission bydetermining, at the WTRU, that the WTRU received a plurality of QCLinformation corresponding to multiple OFDM symbols in the received PDCCHtransmission.
 5. The method of claim 3, wherein the CORESETconfiguration comprises one or more of a CORESET size, a type of REGbundling, a transmission mode, a set of aggregation levels, a set of DCIinformation sizes, a number of PDCCH candidates, the QCL information, oran indication of whether a CORESET is associated with single-beam ormultibeam.
 6. A wireless transmit/receive unit (WTRU) comprising: aprocessor configured to: receive a PDCCH transmission, from a wirelesscommunication system, that comprises a control resource set (CORESET)configuration comprising a resource group (REG) bundle; determinewhether the REG bundle is interleaved within symbols or across symbols;detect the REG bundle by use of a beam corresponding to the REG bundle,if the WTRU determined that the REG bundle is interleaved acrosssymbols; and determine a multibeam PDCCH by use of the detected REGbundle and multiple beams associated with the PDCCH transmission.
 7. TheWTRU of claim 6, where in the processor is further configured todetermine that the REG bundle is bundled in frequency, and determinethat the PDCCH transmission is a multibeam transmission based on thedetermination that the REG bundle is bundled in frequency.
 8. The WTRUof claim 6, wherein the processor being configured to detect the REGbundle further comprises the processor being configured to detect theREG bundle by use of the beam corresponding to the REG bundle and quasicollocated (QCL) information for the REG bundle, if the WTRU determinedthat the REG bundle is interleaved across symbols.
 9. The WTRU of claim6, wherein the processor is further configured to determine that thereceived PDCCH transmission is a multibeam transmission by beingconfigured to determine that the WTRU received a plurality of QCLinformation corresponding to multiple OFDM symbols in the received PDCCHtransmission.
 10. The WTRU of claim 8, wherein the CORESET configurationcomprises one or more of a CORESET size, a type of REG bundling, atransmission mode, a set of aggregation levels, a set of DCI informationsizes, a number of PDCCH candidates, the QCL information, or anindication of whether a CORESET is associated with single-beam ormultibeam.
 11. The WTRU of claim 8, wherein the QCL informationcomprises one or more of average gain, average delay, doppler shift,doppler spread, or spatial receiver parameters.
 12. The WTRU of claim 6,wherein the processor is further configured to detect the REG bundle byuse of PBCH/SYNC beam tracking if the WTRU determined that the REGbundle was interleaved within symbols.
 13. The WTRU of claim 11, whereinthe processor is further configured to determine a single-beam PDCCH bybeing configured to deinterleave the detected REG bundle.
 14. The WTRUof claim 6, wherein the CORESET configuration further comprises anindication of a mode of interleaving REG bundles.
 15. The WTRU of claim14, wherein the processor is further configured to determine from theCORESET configuration whether the mode of interleaving REG bundles isone of time-first bundling without interleaving, time first bundlingwith interleaving, frequency first bundling with per-symbolinterleaving, or frequency first bundling with across symbolinterleaving.